If you dont know who Randy Pausch is, please watch this video. It will change your life forever.

Randy Pausch, the Carnegie Mellon University computer science professor whose final lecture inspired millions, died early today in Virginia of pancreatic cancer.

Dr. Pausch, 47, who turned the lecture into a book, said that no one would have been interested in his words of wisdom were he not a man in his 40s with a terminal illness, leaving behind a wife and three young children.

According to Dr. Pausch's Web site, a biopsy last week revealed that the cancer had progressed further than expected, based on recent PETscans.

"Since last week, Randy has also taken a step down and is much sicker than he had been," the Web site said. "He's now enrolled in hospice. He's no longer able to post here so I'm a friend posting on his behalf because we know that many folks are watching this space for updates."

Last fall, Dr. Pausch delivered the lecture at CMU, which still posts it on its Web site. The lecture has attracted more than six million viewers.

In the year preceding the lecture, he had gone through rounds of chemotherapy and radiation, but refused to give in to morbidity or self-pity. Instead of focusing on the cancer, he talked about how to fulfill childhood dreams and the lessons he learned on his life's journey.

In his 10 years at CMU, he helped found the Entertainment Technology Center, established an annual virtual reality contest and helped start the Alice program, an animation-based curriculum for teaching high school and college students.

After the lecture, he moved to Chesapeake, Va., to spend his remaining time with his wife, children and family.

Steve Seabolt, a vice president at video-game maker Electronic Arts and one of Dr. Pausch's best friends, was with him when he died at 4 a.m. today. Dr. Pausch was lucid until near the end, he said, and even went up and down the steps a couple times at home yesterday, "although he had minimal energy."

Dr. Pausch had stopped taking chemotherapy in recent weeks but was investigating a possible vaccine therapy up until the end of his life, Mr. Seabolt said.

"Randy had an enormous and lasting impact on Carnegie Mellon," said university President Jared L. Cohon. "He was a brilliant researcher and gifted teacher. His love of teaching, his sense of fun and his brilliance came together in the Alice project, which teaches students computer programming while enabling them to do something fun -- making animated movies and games. Carnegie Mellon -- and the world -- are better places for having had Randy Pausch in them."

With the help of Wall Street Journal columnist Jeffrey Zaslow, Dr. Pausch wrote a book, "The Last Lecture," which was published earlier this year and has now been translated into 30 languages. He elaborated on his lecture and emphasized the value he placed on hard work and learning from criticism. His words were intended as a legacy for his young children.

In May, Dr. Pausch spoke at the Carnegie Mellon University commencement. He said a friend recently told him he was "beating the [Grim] Reaper" because it's now been nine months since his doctor told him he would die in six.

"But we don't beat the Reaper by living longer. We beat the Reaper by living well," said Dr. Pausch, who urged the graduates to find and pursue their passion. He put an exclamation point at the end of his remarks by kissing his wife, Jai, and carrying her off stage.

Mr. Zaslow said the commencement was the last time he saw Dr. Pausch. He recalled that Dr. Pausch was weak enough from his cancer that he had to lie down on a couch before and after his appearance, but as he often did, he mustered his energy for the public appearance, "and he was excited and happy."

Mr. Zaslow said he had become obsessed with Googling Dr. Pausch's name each day on the Internet to see how many new Web sites were devoted to him. In an e-mail exchange they had about a month ago, Dr. Pausch "said to me, 'Will you stop Googling me and go hug your kids?' So I did."

In addition to his wife, Dr. Pausch is survived by his children, Dylan, Logan and Chloe. Also surviving are his mother, Virginia Pausch of Columbia, Md., and a sister, Tamara Mason of Lynchburg, Va. The family plans a private burial in Virginia. A campus memorial service is being planned. Details will be announced at a later date. In September, Carnegie Mellon announced a plan to honor Dr. Pausch's memory and his work as "a tireless advocate and enabler of collaboration between artistic and technical faculty members." CMU is to build the Randy Pausch Memorial Footbridge, which will connect the Gates Center for Computer Science, now under construction, with an adjacent arts building.

The family requests that donations on his behalf be directed to the Pancreatic Cancer Action Network, 2141 Rosecrans Ave., Suite 7000, El Segundo, Calif. 90245, or to Carnegie Mellon's Randy Pausch Memorial Fund, which primarily supports the university's continued work on the Alice project.